A Student’s Guide to the Digital World (2009) [pdf]
ocw.mit.edu
ocw.mit.edu
I'm 40, and in the last 9 moths or so I've been able to get back into doing calculus well enough that I can follow these kinds of classes.
That fact has been making the next 40 years or whatever I have a lot more palatable to know that if I want I can enjoy working with this stuff.